package com.imooc.security.rsa;


import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

public class ImoocRSA {

    public static final String src = "imooc security rsa";

    public static void main(String[] args) {
        jdkRSA();
    }

    public static void jdkRSA() {
        try {
            //1.初始化发送方密钥
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
            keyPairGenerator.initialize(512);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
            RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
            System.out.println("Public Key: " + Base64.encodeBase64String(rsaPublicKey.getEncoded()));
            System.out.println("Private Key: " + Base64.encodeBase64String(rsaPrivateKey.getEncoded()));

            //2.私钥加密、公钥解密——加密
            PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] result = cipher.doFinal(src.getBytes());
            System.out.println("私钥加密、公钥解密——加密: " + Base64.encodeBase64String(result));

            //3.私钥加密、公钥解密——解密
            X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
            keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            result = cipher.doFinal(result);
            System.out.println("私钥加密、公钥解密——解密: " + new String(result));


            //4.公钥加密、私钥解密——加密
            x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
            keyFactory=KeyFactory.getInstance("RSA");
            publicKey=keyFactory.generatePublic(x509EncodedKeySpec);
            cipher=Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE,publicKey);
            result=cipher.doFinal(src.getBytes());
            System.out.println("公钥加密、私钥解密——加密: "+Base64.encodeBase64String(result));

            //5.公钥加密、私钥解密——解密
            pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
            keyFactory = KeyFactory.getInstance("RSA");
            privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE,privateKey);
            result=cipher.doFinal(result);
            System.out.println("公钥加密、私钥解密——解密: "+new String(result));
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}
